Automatic carburetor adjustment for burning of different fuels



United States Patent O AUTOMATIC CARBURETOR ADJUSTMENT FOR BURNING OFDIFFERENT FUELS William A. Engstrom, Muskegon, Mich., assignor toContinental Motors Corporation, Muskegon, Mich., a corporation ofVirginia Application July 25, 1955, Serial No. 524,195

2 Claims.- (Cl. 158-36) My invention relates to internal combustionengines and more particularly to a fuel or fuel and air mixture controlfor such engines.

It is necessarily a requirement in engine design to now construct samefor burning a wide variety of fuels, from diesel fuels to high octanegasoline, with the further requirement that same be burned withoutmanual adjustments being required on the carburetor or fuel injector.

It is an object of my present invention to provide for the burning of awide variety of fuels in carbureted engines, as well as in fuelinjection engines, by constructing a control device responsive to thespecific gravity of the fuel being used, which control device may beactuated to automatically adjust the jet of a carburetor or vary thefuel metering control of a fuel injection pump.

For a more detailed understanding of my invention, reference may be hadto the accompanying drawing illustrating a preferred embodiment of myinvention in which like characters refer to like parts throughout theseveral views, and in which- Fig. 1 is a diagrammatic view illustratingthe entire control system,

Fig. 2 is a fragmentary view showing how a nozzle jet of a carburetormay be thus automatically adjusted, and

Fig. 3 is a fragmentary view showing the control system associated witha fuel metering valve of a fuel injection apparatus.

I have chosen to show the control system when applied to a carburetedengine, and referring more particularly to Fig. 1 of the drawing, 10designates an internal combustion engine, 11 thel carburetor, 12 theconventional intake manifold, and 14 the conventional fuel pump.

A fuel supply tank 15 is provided for the storage of any one of a widevariety of fuels and suitable fuel lines 16 are employed to connect thefuel tank to the pump, and the pump outlet to the carburetor.

An auxiliary tank 17 is connected by the fuel line 18 to the supply tank15, this connection being suitably controlled by a conventional oatactuated valve 19, said float 20 located within the auxilitary tank andbeing operated to maintain a constant level of fuel in said auxiliarytank. A oat hydrometer 21 of standard construction is slidably supportedby guides 22, and as well known to those skilled in the art, this oathydrometer is constructed to have a variable disposition in the fueldepending on the specific gravity of the fuel in which it lloats. It isknown that a hydrometer type lloat will sink to various levels in fuelsof various specific gravity, and for example it is noted that a standardoat hydrometer will sink two inches deeper in gasoline than it does injet fuel.

Therefore, the variable relationship of a tloat type hydrometer and theliquid in which it is floated is utilized to operate a mercury switch 25controlling the supply of electric current from battery 26 throughconductors 27 to a solenoid actuator 28.

Referring to Fig. 2 it will be observed that suitable mechanicalconnections 29 from the actuator 28 to the needle valve 30 of thecarburetor 11 are employed to adjust the carburetor jet, whereby toprovide the proper size jet for the fuel being used for operating hteengine. In a fuel injection engine, various types of fuel metering icedevices may be employed to control the discharge of fuel` to the engine,many of these fuel metering devices embodying an angularly adjustablemetering valve 35 of fuel injection pump 40 as illustrated in Fig.y 3.Connections 36 connect the solenoid actuator 28 to the angularlyadjustable fuel metering valve to automatically effect the requiredadjustment for the fuelbeing used to operate the engine.

Any desired type of multiple contact mercury switch Z5 may be employedto control the desired operation of the solenoid actuator 28, and it'will be obvious that various degrees of adjustment may be had if sodesired.

While I have illustrated but one embodiment of my invention, it will beapparent, however, to those skilled in the art to which my inventionpertains that various changes and modifications may be made thereinwithout departing from the spirit of my invention or from the scope' ofthe appended claims. j

I claim: Y

1. In an internal combustion engine, a fuel supply system operable tosupply a combustible fuel charge to said engine and comprising a liquidfuel supply tank, a fuel pump having its inlet connected with said fuelsupply tank, a regulable fuel metering means operable to meter fuel tosaid engine and connected with the fuel outlet of said fuel pump, saidfuel pump supplying fuel under pressure to said fuel metering means, andcontrol means for adjusting said fuel regulable means, said controlmeans comprising an actuator operably connected with said fuel regulablemeans and a specific gravity sensing lloat hydrometer disposed in saidfuel tank and remotely operably connected with said actuator to adjustsame in response to a predetermined change of the specific gravity ofthe liquid fuel in said fuel tank to adjust said fuel metering means inaccordance with said fuel specific gravity, and means maintaining aconstant level of fuel in said fuel tank. t Y

2. In an internal combustion engine, a fuel supply system operable tosupply a combustible fuel charge to said engine and comprising a liquidfuel supply tank, a fuel pump having its inlet connected with said fuelsupply tank, a regulable fuel metering means operable to meter fuel tosaid engine and connected with the fuel outlet of said fuel pump, saidfuel-pump supplying fuel under pressure to said fuel metering means, andcontrol means for adjusting said fuel regulableY means, said controlmeans comprising an actuator operably connected with said fuel regulablemeans and a specific gravity sensing float hydrometer disposed in saidfuel tank and remotely operably connected with said actuator to adjustsame in response to a predetermined change of the specic gravity of theliquid fuel in said fuel tank to adjust said fuelmetering means inaccordance with said fuel specific gravity, said fuel supply tank havinga main tank and an auxiliary tank connected with said main tank andprovided with a oat actuated valve means operable to maintain aVsubstantially constant level of liquid fuel in said auxiliary tank, saidactuator comprising a solenoid operable to adjust said fuel meteringmeans, said oat hydrometer being buoyantly floated in the auxiliary tankfuel supply .and a switch operably connected with'said hydrometer andwith said solenoid and operable to actuate said solenoid in response tochanges of'buoyancy of said hydrometer eifected by predeterminedspecific gravity changes of said fuel.

References Cited in the tile of this patent UNITED STATES PATENTS2,715,831 Catford etal. Aug. 23. 1955 2,930,4az.,V

